This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. 1. Primary objective of this study is to establish testosterone dose-response relationships in surgically menopausal women with low testosterone concentrations for a range of androgen-dependent outcomes, including sexual function, fat-free mass, thigh muscle strength and leg power, several domains of neurocognitive function, plasma lipids, apolipoproteins and lipoprotein particles, and insulin sensitivity. 2. The secondary objective is to determine the range of testosterone doses and subsequent plasma testosterone concentrations that are associated with improvements in sexual, physical and neurocognitive functions and that can be safely administered to women without significant adverse effects.